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Application for PM2812 and PM2813 D - 3
The same is valid for two parallel connected Power Supplies when one Power
Supply is set to the Standby mode. The Standby mode, like the Disable mode, will
try to sink all outputs to 0V. Then the down pro
rammer can also become active
when one Power Supply is still in Operate mode.
Use Coupled Protection for parallel connected channels
When one of the parallel connected channels is shut down by its protection circuit
and the other channels are not, the shut down channel will activate its
to sink the output to 0V. This causes the same effect as
one channel while the others are still enabled.
To prevent this set COUPLE PROT ON for each channel via the AUX key. Disable
Overcurrent Protection for the channels that are used in Constant Current mode.
Note: Coupled Protection is possible only for the channels in the same Power
General advise to pro
ram parallel connected channels
Try to prevent that the down pro
rammer of a channel is continuously
active. This causes unnecessary dissipation and will diminish the lifetime
of the channel.
The best way to prevent the down pro
rammer of a channel to become active is
to use at maximum one channel in Constant Volta
e mode and all other channels
in Constant Current mode. Whether this is possible or not depends on the load
requirements. We will handle the followin
Case 1: Constant Current.
Case 2: Constant Volta
e, Output Current from a fixed minimum value to the
Case 3: Constant Volta
e, Output Current from zero to the maximum.
For all cases it is assumed that there are two or more channels needed to be able
to supply the maximum current.
Case 1: Constant Current
If a fixed current is needed, pro
ram the current settin
of the channels to an
equal part of the required current. Pro
ram all channels, except one, to the
e needed plus a small mar
in to make sure that these channels
will stay in the Constant Current mode. Use the one channel to re
e across the load in the ran
e from 0V to the maximum.